It could be the beginning of a virus or a bacterial wilt. But by the time I have seen that many spots on a plant the leaves are already turning yellow which is the best indication of wilts/virus. I have some plants in the garden that get spots like that, mostly eggplants but each year it varies. It's caused by the tiniest little black bugs, not much bigger than a grain of salt. A beetle I think. Look around the leaves and see what you can find. They don't eat much and I don't harass them unless it gets out of hand. Happy gardening.
